In Davidov U.S. Pat. No. 5,426,915, granted Jun. 27, 1995, there is disclosed a method of and an apparatus for forming envelopes from a standard size sheet of paper by feeding the sheet, cutting from the sheet certain marginal portions, and completing the envelope by applying adhesive to selected portions and folding the same in adherence with other portions.
Japan Patent Disclosure Heisei 9-295475 provides a letter that can be mailed as a first class standard mail without a separate envelope and its manufacturing method. This letter is made of an A4 size three-fold paper. Two overlapping sides of this three-fold paper are adhesively secured. The name and address can be written on an exposed side. A computer generated document can be printed on the same paper that contains the printed name and address, saving an extra time and work of writing the name and address separately.
The present invention relates to methods of folding letter sized sheets of, say A4 paper of the type used for printing in computer controlled printers and copiers, to form a mailing envelope in a manner avoiding the need for cutting any portions of the sheet to be folded.
Such envelopes will be capable of receiving a small number, say up to three or four sheets, depending upon the weight or thickness of the sheets of printed matter.
The foregoing methods are accomplished by folding with respect to a relatively large main, central section of the sheet, portions or flaps which are folded so as to form about the four side edges of the main section a smaller back portion, side portions and a sealing back portion of the envelope.
A number of printed pages of the same size can be folded transversely at a number of locations so that the transversely folded printed page, or pages, if more than one, can be inserted into the envelope before final envelope folding or thereafter.
Typically, in the United States of America, the envelope is pre-formed so that final closure is along a long edge at the top of the envelope, or horizontally with respect to the application of an address and stamp, but in Japan the closure flap is along one long edge, but at one side of the envelope, or vertically, with respect to the application of an address and a stamp.
When the long side of the A4 size rectangular paper is referred to as L, the short side of the rectangular paper is referred to as S, and the width of the adhesive parts on the second back side for a horizontal envelope or on the main right side for a vertical envelope is referred to as P, the original envelope making paper is larger (S-2P)/2 than L/3. It is adequate for a horizontal United States style envelope or a vertical Japanese style envelope. It is especially useful for mechanization of making stuffed envelopes with three-fold printed A4 or other regular paper sizes.
Accordingly, printing upon a sheet of plain, normal letter size paper may be applied in either of the above typical cases and the envelope sheet can be subsequently folded to form the envelope in either case.
The envelope making method makes stuffed envelopes by placing the contents of the envelope on the back of the main envelope side first, before folding. It is adequate for making original envelope papers and their contents of the same size from regular size papers such as A4 papers by using PCs or word processors for the tasks of printing an address on the envelope and a letter to be enclosed. It is useful for mechanizing the process to make stuffed envelopes.